Genomic DNA was purified from 2 ml of human whole blood and eluted in 300 µl elution buffer. The first eluate was loaded onto the column a second time and centrifuged again (i.e., re-eluted). Percentage DNA recovery was calculated by assuming that one leukocyte contains 6.6 pg DNA.

Principle

No phenol–chloroform extraction is required. DNA binds specifically to the QIAamp silica-gel membrane while contaminants pass through. PCR inhibitors, such as divalent cations and proteins, are completely removed in two efficient wash steps, leaving pure nucleic acid to be eluted in either water or a buffer provided with the kit. QIAamp DNA Blood technology yields genomic, mitochondrial, or viral DNA from blood and related body fluids ready to use in PCR and blotting procedures.

Procedure

The QIAamp DNA Blood Midi Kit simplifies isolation of DNA from blood and related body fluids with a fast spin-column procedure (see flowchart "procedure"). Fresh and frozen whole blood with common anticoagulants, such as EDTA, citrate, or heparin, may be processed. The QIAamp DNA Blood Midi Kit processes sample sizes of 0.3–2 ml, with a preparation time of 55 minutes. The typical yield from 1 ml healthy whole blood is 20–60 µg, with an elution volume of 100–400 µl.

QIAamp DNA Blood Kits are supplied with a comprehensive handbook containing protocols for DNA isolation from a number of sample sources. QIAamp sample preparation technology is fully licensed.